ANALOG DEVICES AD8273 Service Manual
Dual-Channel,
V
www.BDTIC.com/ADI
FEATURES
Two gain settings
Gain of ½ (−6 dB)
Gain of 2 (+6 dB)
0.05% maximum gain error
10 ppm maximum gain drift
Excellent ac specifications
20 V/μs minimum slew rate
800 ns to 0.01% settling time
Low distortion: 0.004%, 20 Hz to 20 kHz
High accuracy dc performance
77 dB minimum CMRR
700 μV maximum offset voltage
14-lead SOIC package
Supply current: 2.5 mA maximum per channel
Supply range: ±2.5 V to ±18 V
APPLICATIONS
High performance audio
Instrumentation amplifier building blocks
Level translators
Automatic test equipment
Sin/Cos encoders
GENERAL DESCRIPTION
The AD8273 is a low distortion, dual-channel amplifier with
internal gain setting resistors. With no external components,
it can be configured as a high performance difference amplifier
(G = ½ or 2), inverting amplifier (G = ½ or 2), or noninverting
amplifier (G = 1½ or 3).
The AD8273 operates on both single and dual supplies and only
r
equires 2.5 mA maximum supply current for each amplifier.
It is specified over the industrial temperature range of −40°C to
+85°C and is fully RoHS compliant.
Audio Difference Amplifier
AD8273
FUNCTIONAL BLOCK DIAGRAM
+
S
11
12kΩ
2
12kΩ
3
12kΩ
6
12kΩ
58
Table 1. Difference Amplifiers by Category
Low
Distortion
High
Voltage
AD8270 AD628 AD8202 AD8205
AD8273 AD629 AD8203 AD8206
AMP03 AD8216
6kΩ
12
13
6kΩ
14
6kΩ
10
9
6kΩ
4
–V
S
Figure 1.
Single-Supply
Unidirectional
06981-001
Single-Supply
Bidirectional
Rev. 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700 www.analog.com
Fax: 781.461.3113 ©2008 Analog Devices, Inc. All rights reserved.
AD8273
www.BDTIC.com/ADI
TABLE OF CONTENTS
Features.............................................................................................. 1
Applications....................................................................................... 1
General Description ......................................................................... 1
Functional Block Diagram .............................................................. 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 4
Maximum Power Dissipation..................................................... 4
ESD Caution.................................................................................. 4
REVISION HISTORY
1/08—Revision 0: Initial Version
Pin Configuration and Function Descriptions..............................5
Typical Performance Characteristics..............................................6
Theory of Operation ...................................................................... 11
Configurations............................................................................ 11
Power Supplies............................................................................ 11
Outline Dimensions....................................................................... 13
Ordering Guide .......................................................................... 13
Rev. 0 | Page 2 of 16
AD8273
www.BDTIC.com/ADI
SPECIFICATIONS
VS = ±15 V, V
Table 2.
Parameter Conditions Min Typ Max Unit
DYNAMIC PERFORMANCE
Bandwidth 20 MHz
Slew Rate 20 V/μs
Settling Time to 0.1% 10 V step on output, CL = 100 pF 670 750 ns
Settling Time to 0.01% 10 V step on output, CL = 100 pF 750 800 ns
Channel Separation f = 1 kHz 130 dB
NOISE/DISTORTION
THD + Noise f = 1 kHz, V
Noise Floor, RTO
Output Voltage Noise (Referred to Output) f = 20 Hz to 20 kHz 3.5 μV rms
f = 1 kHz 26 nV/√Hz
GAIN
Gain Error 0.05 %
Gain Drift −40°C to +85°C 2 10 ppm/°C
Gain Nonlinearity V
V
INPUT CHARACTERISTICS
3
Offset
vs. Temperature −40°C to +85°C 3 μV/°C
vs. Power Supply VS = ±2.5 V to ±18 V 2 10 μV/V
Common-Mode Rejection Ratio VCM = ±40 V, RS = 0 Ω, referred to input 77 86 dB
Input Voltage Range
Impedance
Differential VCM = 0 V 36 kΩ
Common Mode
OUTPUT CHARACTERISTICS
Output Swing −VS + 1.5 +VS − 1.5 V
Short-Circuit Current Limit Sourcing 100 mA
Sinking 60 mA
Capacitive Load Drive G = ½ 200 pF
G = 2 1200 pF
POWER SUPPLY
Supply Current (per Amplifier) 2.5 mA
TEMPERATURE RANGE
Specified Performance −40 +85 °C
1
Includes amplifier voltage and current noise, as well as noise of internal resistors.
2
dBu = 20 log (V rms /0.7746).
3
Includes input bias and offset current errors.
4
May also be limited by absolute maximum input voltage or by the output swing. See the Absolute Maximum Ratings section and Figure 9 through Figure 12 for
details.
5
Internal resistors are trimmed to be ratio matched but have ±20% absolute accuracy.
6
Common mode is calculated looking into both inputs. Common-mode impedance looking into only one input is 18 kΩ.
= 0 V, TA = 25°C, G = ½, RL = 2 kΩ, unless otherwise noted.
REF
1
2
= 10 V p-p, 600 Ω load 0.004 %
OUT
20 kHz BW −106 dBu
= 10 V p-p, 600 Ω load 200 ppm
OUT
= 5 V p-p, 600 Ω load 50 ppm
OUT
Referred to output 100 700 μV
4
5
6
−3VS + 4.5 +3VS − 4.5 V
9 kΩ
Rev. 0 | Page 3 of 16
AD8273
www.BDTIC.com/ADI
ABSOLUTE MAXIMUM RATINGS
Table 3.
Parameter Rating
Supply Voltage ±18 V
Output Short-Circuit Current
Voltage at Any Input Pin 40 V
Differential Input Voltage 40 V
Current into Any Input Pin 3 mA
Storage Temperature Range −65°C to +130°C
Specified Temperature Range −40°C to +85°C
Thermal Resistance
θJA 105°C/W
θJC 36°C/W
Package Glass Transition Temperature (TG) 150°C
Observe
ating curve
der
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
MAXIMUM POWER DISSIPATION
The maximum safe power dissipation for the AD8273 is limited
by the associated rise in junction temperature (T
approximately 150°C, which is the glass transition temperature,
the plastic changes its properties. Even temporarily exceeding
this temperature limit may change the stresses that the package
exerts on the die, permanently shifting the parametric performance
of the amplifiers. Exceeding a temperature of 150°C for an
extended period can result in a loss of functionality.
The AD8273 has built-in, short-circuit p
rotection that limits the
output current to approximately 100 mA (see Figure 2 for more
info
rmation). While the short-circuit condition itself does not
damage the part, the heat generated by the condition can cause
the part to exceed its maximum junction temperature, with
corresponding negative effects on reliability.
2.0
1.6
1.2
) on the die. At
J
TJ MAX = 150°C
θ
= 105°C/W
JA
0.8
0.4
MAXIMUM POWER DISSIPATION (W)
0
–50 –25 0 25 50 75 100 125
AMBIENT TEMPERATURE (°C)
Figure 2. Maximum Power Dissipation vs. Ambient Temperature
06981-043
ESD CAUTION
Rev. 0 | Page 4 of 16
AD8273
www.BDTIC.com/ADI
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
1
NC
2
–12A
+12A
3
–V
4
S
+12B
5
6
–12B
7
NC
NC = NO CONNECT
AD8273
TOP VIEW
(Not to Scale)
14
+6A
13
OUTA
–6A
12
+V
11
S
–6B
10
9
OUTB
8
+6B
06981-020
Figure 3. Pin Configuration
Table 4. Pin Function Descriptions
Pin No. Mnemonic Description
1, 7 NC No Connect.
2 −12A The 12 kΩ resistor connects to the negative terminal of Op Amp A.
3 +12A The 12 kΩ resistor connects to the positive terminal of Op Amp A.
4 −VS Negative Supply.
5 +12B The 12 kΩ resistor connects to the positive terminal of Op Amp B.
6 −12B The 12 kΩ resistor connects to the negative terminal of Op Amp B.
8 +6B The 6 kΩ resistor connects to the positive terminal of Op Amp B.
9 OUTB Op Amp B Output.
10 −6B The 6 kΩ resistor connects to the negative terminal of Op Amp B.
11 +VS Positive Supply.
12 −6A The 6 kΩ resistor connects to the negative terminal of Op Amp A.
13 OUTA Op Amp A Output.
14 +6A The 6 kΩ resistor connects to the positive terminal of Op Amp A.
Rev. 0 | Page 5 of 16
Loading...